Due to technological advancements, additional electronic devices, such as digital televisions (DTV), global positioning systems (GPS), radios, and the like, are increasingly mounted inside a car body, so are the integrated functions thereof. The electronic devices receive and transmit signals by an antenna structure.
Conventional vehicular antenna structures come in the following categories, printed antennas mounted on windows of vehicles, extensible antennas mounted at the rear ends of vehicles, and fixed antennas (such as shark-fin antennas and rod-shaped antennas) mounted on the tops of vehicles.
However, the aforesaid conventional vehicle antenna structures have disadvantages. For example, the printed antennas cannot be easily mounted on the windows of the vehicles, nor are they efficient in receiving signals, because the thermal insulating sheets on the windows using contain metals. Both the extensible antennas and the fixed antennas are mounted on the surfaces of the car bodies and thus may get damaged readily to the detriment of the beauty of the car bodies. Accordingly, there is still room for improving the prior art.